Nobody knows if some sort of bargain has been made, but it is interesting that Rep. Ron Paul has never really attacked Mitt Romney, yet he has frequently attacked more conservative candidates at just the moment they were beginning to pose a threat to Romney. (For example, consider his latest ad, attacking Rick Santorum.)

Kentucky’s junior senator says it would be an honor to be
considered as a possible running mate for Republican presidential
candidate Mitt Romney.
… After a speech in Louisville today, [Sen. Rand] Paul held that door firmly open, saying he wants to be part of the national debate.

… “I don’t know if I can answer that question, but I can say it would be an honor to be considered,” he said.